ANIMA CANDIDA
encouragement. The Lord may have known that if ever a
struggling mortal needed encouragement, poor Riemann did;
still, it seems rather an odd way of providing what was required.
In 1S5S Riemann produced his paper on electrodynamics, of
which he told his sister Ida, 'My discovery concerning the close
connexion between electricity and light I have dedicated to the
Royal Society [of Gottingen]. From what I have heard, Gauss
had devised another theory regarding this close connexion,
diHerent from mine, and communicated it to his intimate
friends. However, I am fully convinced that my theory is the
correct one, and that in a few years it will be recognized as such,
As is known, Gauss soon withdrew his memoir and did not
publish it; probably he himself was not satisfied with it.'
Riemann would seem here to have been over-optimistic; Clerk
Maxwell's electromagnetic theory is the one which to-day holds
the field - in macroscopic phenomena. The present status of
theories of light and the electromagnetic field is too complicated
to be described here; it is sufficient to note that Riemann's
theory has not survived.
Dirichlet died on 5 May 1859. He had always appreciated
Riemann and had done his best to help the struggling young
man along. This interest of Dirichlet's and Riemann's rapidly
mounting reputation caused the government to promote
Riemann to succeed Dirichlet. At thirty-three Riemann thus
became the second successor of Gauss. To ease his domestic
difficulties the authorities let him reside at the Observatory, as
Gauss had done. Recognition of the sincerest kind - praise from
mathematicians who, although older than himself, were in some
degree his rivals - now came in abundance. On a visit to Berlin
he was feted by Borchardt, Kurnmer, Kronecker, and Weier-
strass. Learned societies, including the Royal Society of
London and the French. Academy of Sciences, honoured him
with membership, and in short he got the usual highest distinc-
tions that can come to a man of science. A visit to Paris in 1860
acquainted him with the leading French mathematicians,
particularly Hermite, whose admiration for Riemann was
unbounded. This year, 1860, is memorable in the history of
mathematical physics as that in which Riemann began inten-
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